Answers

It looks like what is marketed here in the spring as Easter Lilies, White and very showy, most people can't keep them growing because the humidity is too high in the southern US. Used for Mother's Day sometimes also for cemetery decorations.

There is no reason why they should not survive. If they were in the ground when you moved into the flat they may have been there quite some time. I grow them in pots because slugs usualy eat them, but they last for several years.

Lilies or some sort :) At least 9 bulbs in the photo. Are the stalks furry? I have several different lilies; but my fav the tiger lily, the stalks are covered with a white fur. They look happy and heathy where they are.